QuickView for sulfamethoxazole (compound)

Summary
General Info

PubChem

PubChem Compound 11953892

Name:	Sulfamethoxazole
PubChem Compound ID:	11953892
Description:	A bacteriostatic antibacterial agent that interferes with folic acid synthesis in susceptible bacteria. Its broad spectrum of activity has been limited by the development of resistance. (From Martindale, The Extra Pharmacopoeia, 30th ed, p208)
Molecular formula:	C₉H₁₀N₄O₃S
Molecular weight:	254.267 g/mol
Synonyms:	723-46-6; Sulfamethoxazole; D00447; Gantanol (TN); Gantanol; Sulfamethoxazole (JP15/USP); C07315

DrugBank

Identification

Name:	Sulfamethoxazole
Name (isomeric):	DB01015
Drug Type:	small molecule
Description:	A bacteriostatic antibacterial agent that interferes with folic acid synthesis in susceptible bacteria. Its broad spectrum of activity has been limited by the development of resistance. (From Martindale, The Extra Pharmacopoeia, 30th ed, p208)
Brand:	Gantanol, Gamazole, Radonil, Apo-Sulfamethoxazole, Sulphamethoxazole BP 98, Bactrimel, Azo-Gantanol, Sulfamethylisoxazole, Azo Gantanol, Sulfamethoxizole, Sulfisomezole, Sulphamethoxazol, Sulfamethalazole, Sulphamethoxazole, Sinomin, Sulfamethoxazol, Sulpha-Methoxizole, Sulphisomezole, SIM, Urobak, Septran, Sulphamethalazole, Metoxal, Gantanol-DS, Simsinomin, Trib, Sulphamethylisoxazole
Brand name mixture:	Bactrim Roche Suspension Paediatric(Sulfamethoxazole + Trimethoprim), Roubac Tab 80/400(Sulfamethoxazole + Trimethoprim), Septra DS Tablets(Sulfamethoxazole + Trimethoprim), Apo Sulfatrim DS Tab(Sulfamethoxazole + Trimethoprim), Novo-Trimel Oral Sus(Sulfamethoxazole + Trimethoprim), Riva-Sep DS(Sulfamethoxazole + Trimethoprim), Bactrim DS Roche ... show more » Bactrim Roche Suspension Paediatric(Sulfamethoxazole + Trimethoprim), Roubac Tab 80/400(Sulfamethoxazole + Trimethoprim), Septra DS Tablets(Sulfamethoxazole + Trimethoprim), Apo Sulfatrim DS Tab(Sulfamethoxazole + Trimethoprim), Novo-Trimel Oral Sus(Sulfamethoxazole + Trimethoprim), Riva-Sep DS(Sulfamethoxazole + Trimethoprim), Bactrim DS Roche Tab(Sulfamethoxazole + Trimethoprim), Protrin Tab(Sulfamethoxazole + Trimethoprim), Apo Sulfatrim Pediatric(Sulfamethoxazole + Trimethoprim), Septra Pediatric Suspension(Sulfamethoxazole + Trimethoprim), Novo-Trimel DS Tab(Sulfamethoxazole + Trimethoprim), Septra(Sulfamethoxazole + Trimethoprim), Roubac Tab 160/800(Sulfamethoxazole + Trimethoprim), Bactrim Roche Inj(Sulfamethoxazole + Trimethoprim), Sulfamethoxazole and Trimethoprim Tablets(Sulfamethoxazole + Trimethoprim), Apo Sulfatrim Tab(Sulfamethoxazole + Trimethoprim), Novo-Trimel Tab(Sulfamethoxazole + Trimethoprim), Septra Injection(Sulfamethoxazole + Trimethoprim), Bactrim Roche Tab(Sulfamethoxazole + Trimethoprim), Protrin DF Tab(Sulfamethoxazole + Trimethoprim) show less «
Category:	Anti-Infective Agents, Sulfonamides, Anti-Infectives
CAS number:	723-46-6

Pharmacology

Indication:	For the treatment bacterial infections causing bronchitis, prostatitis and urinary tract infections.
Pharmacology:	Sulfamethoxazole is a sulfonamide drug that inhibits bacterial synthesis of dihydrofolic acid by competing with para-aminobenzoic acid (PABA) for binding to dihydropteroate synthetase (dihydrofolate synthetase). Sulfamethoxazole is bacteriostatic in nature. Inhibition of dihydrofolic acid synthesis decreases the synthesis of bacterial nucleotides a... show more » Sulfamethoxazole is a sulfonamide drug that inhibits bacterial synthesis of dihydrofolic acid by competing with para-aminobenzoic acid (PABA) for binding to dihydropteroate synthetase (dihydrofolate synthetase). Sulfamethoxazole is bacteriostatic in nature. Inhibition of dihydrofolic acid synthesis decreases the synthesis of bacterial nucleotides and DNA. Sulfamethoxazole is normally given in combination with Trimethoprim, a dihydrofolate reductase inhibitor, which inhibits the reduction of dihydrofolic acid to tetrahydrofolic acid. Studies have shown that bacterial resistance develops more slowly with the combination of the two drugs than with either Trimethoprim or Sulfamethoxazole alone. show less «
Mechanism of Action:	Sulfonamides inhibit the enzymatic conversion of pteridine and p-aminobenzoic acid (PABA) to dihydropteroic acid by competing with PABA for binding to dihydrofolate synthetase, an intermediate of tetrahydrofolic acid (THF) synthesis. THF is required for the synthesis of purines and dTMP and inhibition of its synthesis inhibits bacterial growth. Pyr... show more » Sulfonamides inhibit the enzymatic conversion of pteridine and p-aminobenzoic acid (PABA) to dihydropteroic acid by competing with PABA for binding to dihydrofolate synthetase, an intermediate of tetrahydrofolic acid (THF) synthesis. THF is required for the synthesis of purines and dTMP and inhibition of its synthesis inhibits bacterial growth. Pyrimethamine and trimethoprim inhibit dihydrofolate reductase, another step in THF synthesis, and therefore act synergistically with the sulfonamides. show less «
Absorption:	Rapidly absorbed following oral administration. Also well-absorbed topically.
Protein binding:	70%
Biotransformation:	Hepatic. The metabolism of sulfamethoxazole occurs predominately by N4-acetylation, although the glucuronide conjugate has been identified.
Half Life:	10 hours
Toxicity:	Sulfamethoxazole may cause nausea, vomiting, diarrhea and hypersensitivity reactions. Hematologic effects such as anemia, agranulocytosis, thrombocytopenia and hemolytic anemia in patients with glucose-6-phosphate dehydrogenase deficiency may also occur. Sulfamethoxazole may displace bilirubin from albumin binding sites causing jaundice or kernicterus in newborns.
Affected organisms:	Gram negative and gram positive bacteria

Interactions

Food interaction:

Do not take calcium, aluminium, magnesium or iron supplements within 2 hours of taking this medication.

Take on empty stomach: 1 hour before or 2 hours after meals.

Take with a full glass of water.

Drug interaction:

Cyclosporine	The sulfonamide decreases the effect of cyclosporine
Chlorpropamide	Sulfonamide/sulfonylurea: possible hypoglycemia
Tobramycin	Increased risk of nephrotoxicity
Warfarin	Sulfamethoxazole may increase the anticoagulant effect of warfarin by decreasing its metabolism. Consider alternate therapy or monitor for changes in prothrombin time if sulfamethoxazole is initiated, discontinued or dose changed.
Tolbutamide	Tolbutamide, a strong CYP2C9 inhibitor, may decrease the metabolism and clearance of Sulfamethoxazole. Consider alternate therapy or monitor for changes in Sulfamethoxazole therapeutic and adverse effects if Tolbutamide is initiated, discontinued or dose changed.

Targets

Dihydropteroate synthase

FolC bifunctional protein [Includes: Folylpolyglutamate synthase

Enzymes

Arylamine N-acetyltransferase 1

Arylamine N-acetyltransferase 2

Cytochrome P450 2C9

Prostaglandin G/H synthase 1

UDP-glucuronosyltransferase 1-9

Cytochrome P450 2C8

Cytochrome P450 3A4

Carriers

Serum albumin